Subscribe
the Legacy continues…………………….
Gregory R. Mann, Ph.D. {ret.}

Spinner Shark

“Carcharhinus brevipinna”

Spinner Sharks are so named for their unique hunting technique. They swim very fast after their prey, spinning as they do so and regularly leaping from the water. Their spinning leaps occur after shooting after prey, snapping & spinning as they go. Spinner Sharks have a wide range, occurring in warm-temperate to tropical waters in the Atlantic, Pacific and Indian Oceans. They live along the continental shelves and frequently come in close to the shore. They are known to be migratory off the coast of the United States and probably elsewhere. They tend to move closer to the coast during the breeding season in the spring & summer. During the breeding season, Spinner Sharks have a few live young. Unlike bony fish of a comparable size they reproduce slowly. Rather than thousands of eggs their offspring begin life as 2 foot long shark pups, which gives each individual a better chance of survival. Males mature at about the age of 4 and females a little later at 7 or 8. Estimates based on the size of large Spinner Sharks (up to 8 feet), puts the maximum age at least twenty and probably much more.

Spinner Sharks are schooling sharks and segregate themselves by gender & age. This is a common behavior in many sharks but we still don’t know the exact reason for it.  Mutual protection is probably the main reason for schooling but why they separate themselves into all male and all female groups is uncertain. Their diet is varied including bony fish, small sharks, octopus, squid & cuttlefish. They have small, sharp teeth and go for smaller prey. Large mammals including humans, are too big to feature in their diet. Spinner Sharks have been recorded for a handful of unprovoked attacks on humans, usually associated with spear fishing divers but no known fatalities. In general they are considered relatively harmless. Predators of Spinner Sharks are few with larger species of sharks probably posing the main natural threat, especially to juveniles.  

Advertisements